Index: The conflict between Christianity (for once differing between catholisism, protestantism, etc) and science. The Christians use magic, the science side has developed a way to produce esper powers.
Railgun: The internal conflicts within Academy City, the scientific capital of the world.

I too prefer Index, but that's because it features Touma and Misaka interacting more often.

And Railgun really isn't moeblob, it looks that way, but only on the surface. It doesn't really have that much less good action than Index either, there's just a less clear boundary between the daily life and the action.
Also the Sisters arc was important, though it may not seem that way for those interested mostly in the action. It serves to show Misaka's side of the story and offers great exposition of why this event had such a big impact on her character as a whole and on her opinion of Touma. During the Sisters arc of Index, it was all about saving just the sisters. This time we saw that in reality, he saved Misaka as well.

I'd say the speeches are a plus in Index case. They may have been done to death in shounens, but unlike every single case of that, Touma actually poses moral questions that hit home with the viewer, instead of reason-why-I'll-win speeches like Naru

And don't call Misaka just a tomboy, she's a shorttank, the best kind of tomboy.

There's the problem that according to what I've gathered from spoilers on TVTropes, Misaka will soon get an upgrade from supporting character to main character in Index, meaning they have to finish establishing her background until it's at least close to up to date with Index, and there's one REALLY important event that takes place during her side of the Dahaseisai.

And I too hate K-On and similar moeblobs, and the cutesy filler did annoy me in the first season, but most of it has been done away with in Railgun S.

I'm still waiting for Index to get back on track and actually be about, ya know... the ******* person it's named for. She barely makes appearances in the second season. Like, she falls in love with dude, dude falls in love with her, dude loses memory, then... nothing? Suddenly the entire foundation of the story is dropped like a bag full of scorpions and no effort is made to get back on track.

Touma didn't fall in love with her. Touma just did what he always does; save the damsel in distress. She's there as a little sister character and a plot device, someone to be protected, not a romantic interest or fighter.

I was never a big fan of Index, her personality seems to only involve biting Touma, complaining about food, and liking Touma. Personally I feel like there should have been more Touma x Biribiri. (makasi, misaka maraca whatever her name was)

Innocent, reliant on others, always hungry, overly curious, tsundere, high-and-mighty, McGyver-ey, borderline technophobic...
She's got more than 3. But yeah she boils down to base character traits because of the lack of memories. That kind of was the point of her memories being erased in the first place; to prevent her from getting any ideas of her own.

Ok, sure but you gotta admit, considering the show is supposed to be about her, she's hardly ever there and her character would be a lot fuller if they actually gave her some screen time to develop as a person. Instead it's basically implied that she's just sitting at home eating while Touma risks his life everywhere and anywhere.

It's not supposed to be about her though. It's about Touma and the war between science and religion. Index is just the plot device that got the ball rolling.
And no, it's not implied that she's just eating. It's shown that she worries and would help if she could, but Touma tries to keep her in th dark to protect her.

Though she's not exactly playing the most minor role either, she often gets past Touma's attempts to keep her out of things, like when she went together with Accelerator during the Invasion arc and ended up being the one who saved the day.

Well, Railgun covers mostly (in a sense) government corruption. It's really five girls who stop some form of crime that escalates further to the major villain or plot point. The only real sex jokes are from Kuroko (the one with the annoying hair that's everywhere), she is only that way towards Misaka. The jokes are just to lighten the serious atmosphere from time to time. It's a good series overall and is better than Index (unpopular personal opinion).